Pesticides Worse For Kids

| Tue Jul. 21, 2009 4:13 PM EDT

Scientists have suspected for a while that like many substances, pesticides affect children and adults differently. It stands to reason: Kids have less mass to absorb chemicals, and their organs are still developing. But it's hard to figure out exactly how toxins interact with children's bodies—or how dangerous they are.

Some encouraging news: A team of U.C. Berkeley researchers  pinpointed an enzyme—called paraoxonase—that helps the body break down organophosphate pesticides. They found that until children reach age seven, they don't have nearly as much of the enzyme as adults do:

Although it has been known that newborns have low levels of the paraoxonase enzyme, it was previously believed that paraoxonase concentrations reached adult levels by 2 years of age.

This assumption was based on one earlier study of 9 children. Now a new study of 458 children followed from birth to age 7 shows that paraoxonase levels continue to increase steadily until age 7. At age 7, the average paraoxonase level in children was similar to, but still lower than, adult levels.

The bad news: Organophosphates are cheap, and this mosquito season, an inexpensive pesticide will look awfully appealing to financially strapped cities.